Synchronizing and speed control system and mechanism



Mayv 25, 1937.

H. l. TURNER ET Al.

SYNCHRONIZING AND SPEED CONTROL SYSTEM AND MECHANISM Original FiledvDec. 5, 1934 O6 v OOO' |008 IOIO l/OOZ O|4 IOIZ @iene TO OTHER "om "O32MEOH'ANlsMs AT OTHER flole H054 LOCAL 05" ,i030 CONTROLLERS MASTER TIMERu-"Tees@ MECHANlsMs AT A LOCAL CONTROLLER SYNCHRO- 320- 3.@ ggg TRL im42 29o 48o- @CAM 3|'Z/ 30 MT' 306 I 2% 30o 50e' Qca Qaoe ROT TMT 3041 IA Es O 204 VARY sPEE I l l l l L .1 zo 4,22 @24 ce2@ @ze @so L zaabzf.LOCAL 650 g CONTROLLER L ,i @edl OQO; Ien/,91H Q52] SPEQIAL SU PLY FOFlMOTQRIMI VQ;- E lI G4- @e4 36%/ UNEF-gg 'N8 670 1 -Q70 INVENTORSHARRlSON l. TURNER l 'Ezl F668, I CARL L. ANDERSON IL Il-67o BY 766m/ATTORNEY Patented May 25, 1937l accises SYNCHRONIZHNG AND SPEED CGNFRLSYSTEM AND MECHNESIi/ Harrison iirving Turner and Cari son, Moline,Ill., poration, chusetts Original Ludwig Anderassignors to Eagle SignatCor- Moline, Ill.,

a corporation of Massaapplication December 3,1934, seriai No. 755,742.Divided and this application November 14, 1935, Serial No. 49,76@

'i Ciairnsu This .invention relates to synchronizing and speed controlsystems and mechanisms, and more particularly to such systems andmechanisms as those utilized ,for governing the operation of a pluralityof electric highway trafc signal controllers in situations where it isdesirable to maintain preselected speeds and coordination oi operationbetween such controllers while permitting variations of durations and/orcharacter- I) istics of components entering into cycles of changes ofsignal aspects irrespective of the character of electric currentutilized.

Such synchronizing and speed control systems and mechanisms heretoforeavailable for governi ing the operation of highway traiiic controllershave embodied characteristics which precluded variations of cycledurations as well as accurate synchronism therebetween and, to attainmost perfect results, have necessitated utilization of electric currentof special character.

Furthermore, the complex and intricate character of synchronizing andspeed control systems and mechanisms which have heretofore been suppliedfor such service has resulted inthe dei sign and utilization ofmechanism subject to disarrangementA and, when disarranged, requiringhighly skilled services for effecting repair and readjustment.

It is therefore an important object of this in-l vention to provide suchsystems and mechanisms for associating a local highway trac signalcontroller with a master timer, which systems and mechanisms are capableof periodically and automatically effecting and maintaining synchronicalrelationship between said local controller and said master timer bysynchronizing the operation and correcting the operating speed of saidlocal controller.

Another important object of this invention is to provide such systemsand mechanisms which are capable of periodically and automaticallyeffecting needed revisions in the operating speed of said localcontroller, whereby to maintain substantially synchronical speed betweenthe operation of said local controller and that of said master timer.

Another object of this invention is tov provide such systems andmechanisms for association with a local highway trafc signal controlleras will be capable of periodically and automatically effecting revisionsin the speed of operation of such local controller necessarytovcompensate for any change in speed therein such as may rel sult fromatmospheric temperature variations or otherwise. fg

(CHL. .w25-293) Another. important object oi this'invention is toprovide such systems and mechanisms in association with local highwaytrahie signai con.- trollers at a plurality of traiiic laneintersections whereby to govern the operating speeds of the respectivecontroller in such relationship to a master timer as to cause displayssignal aspects at respective lane intersections facilitating progressivemovement of trails. l

Another important object of this invention is to provide such systemsand mechanisms for aslsociation with local highway trailc signalcontrollers at a plurality of traffic lane intersections whereby toestablish, periodically and automatically, concurrent attainment ofpredetermined synchronizing stages of respective controllers andthereafter act to maintain predetermined relationships between ensuingoperative stages of respective controllers through automaticaccomplishment of needed operating speed revisions at each localcontroller.,

Another vinmortant object of this invention is to provide such systemsand mechanisms which, irrespective of the character of the electriccurrent employedV for actuation thereof, may be utilized forestablishing the times of occurrence of a predetermined operative stageand for maintaining predetermined relatlonships between such stage andother operative stagesa A further important object of this invention isto provide such improved systems and mechanisms which, for theaccomplishment or all, any one or any group of the foregoing objectsshall be of greater effectiveness and reliability, composed of a smallernumber of parts severally characterized by strength', durabilityand'facility of assemblage, as well as amenable to a lower cost ofmanufacture.

Other and more specific objects and' advantages will appear in thefollowing description of an illustrative embodiment of this invention,or will be apparent to those skilled in this art.

A traic signal system including a local highway traiic signal controllerof a type with which this invention may be employed is fully shown anddescribed in the zzo-pending application oi Harrison Irving Turner andCarl Ludwig Anderson, the present applicants, tiled December 3rd, 1934,Serial No. 755,742, for Signal Controlling and duration varying systemsand mechanisms therefor, in which application this invention wasoriginally disclosed and of which application this is a divison. A

Detailed description of the circuits and mechanism of such trafficsignal system will-therefore be herein omitted.

In a preferred embodiment of this invention, the foregoing objects andothers ancillary thereto are preferably accomplished as follows:

A master timer comprises mechanism for electrically energizing anddeenergizing two channels which are associated with one or more localhighway trafilc signal controllers; such eneagizations anddeenergizations of channels occurring independentlyl at regularpredetermined intervals and continuing for regular predetermineddurations.

Such highway trafllc signal controllers may be of any desired type whichis governed by a variable speed motor. In accordance with thisinvention, speed regulating means is associated with the motor of eachsuch controller, which regulating means preferably compriseselectrically operable actuating means, a speed revision determining cam,and contacts for actuation by the respective cams.

Said actuating means preferably comprises two motors applied foractuating mechanism associated with the controller motor so thatrespective ones of said driving means motors may be energized foreffecting increase or decrease of the operating speed of its associatedcontroller motor.

Should the speed of the controller governing motor be such as to causeattainment of a predetermined stage in the operatio'nfof the speedrevision determining cam substantially in advance of a timepreestablished therefor by the master timer, one of the master timerchannels will be energized whereby one of the speed regulating motorswill be energized to effect mechanism alterations such as will retardthe operating speed of the controller governing motor.

Should the controller governing motor so operate as to cause attainmentof another predeterv mined stage inthe operation of the speed revisiondetermining cam at a time substantially later than that preestablishedtherefor by the master timer, said one of the master timer channels willbe energized whereby the other of the speed regulating motors will beenergized to effect mechanism alterations such as will increase oraccelerate the operating speed of the controller governing motor.

Should said controller governing motor so operate as to cause attainmentof still another predetermined stage in the operation of the speedrevision determining cam at a time substantial-- ly co-extensive withthe time during which said one of the master timer channels isenergized, neither of the speed regulating motors will be energized andoperation of the controller governing motor will continue withoutalteration of the speed thereof.

A synchronizing cam is associated with the remaining master timerchannel and, upon attaining a predetermined stage, interrupts the normalcurrent supply path to the controller governing motor whereupon shouldsaid motor be out of synchronism by a substantial amount it will bebrought to rest and will be ,restarted only upon deenergization of saidremaining master timer channel. Such deenergization will result ineffective establishment of a special current supply path for said motor.

Should the synchronizing cam attain the foregoing predetermined stageAsubstantially simultaneously with or immediately following thedeenergization of the said remaining master timer 4 bodiment, thoughpractical, is by no means the only one which the invention may assume,wherefore the invention is not confined to any strict conformity withthe more or less diagrammatic representation of the drawing but may bechanged and modified in various particulars so long as such changes andmodifications make no material departures from the invention, as moreparticularly set forth in the annexedlaims.

In the accompanying drawing, reference characters employed in theaforementioned application of which this is a division have been largelyso employed as to facilitate comparison therewith, and like parts aredesignated by the same reference characters throughout the several viewsin which Figure 1 is a schematic "across-the-line" representation ofcircuit connections combined with a diagrammatic presentation ofmechanisms and an arrangement of parts embodying this invention; and

Fig. 2 is a composite chart representative of various operating andcircuit characteristics of an embodiment of this invention in comparisonwith those of a master timer.

In Fig. 1 of the drawing, mechanism and circuits indicated below a dashline h are for association with a local traillc signal controller. Suchcircuits and mechanism comprise a shaft 204 rotatable for establishingsignal cycle durations and times of occurrence thereof for theassociated local controller such as will be in predeterminedrelationship to cycles of other like controllers.

The shaft 204 is driven by means of an electric motor which may be of atype operable by direct current or of a type operable by alternatingcurrent. For convenience, such motor is indicated in the drawing as analternating current` induction type motor Mi comprising an electromagnet290, a disc 292, a shaft 294, a worm gear 296 and a worm wheel 298; saidwheel 298 being secured to shaft 204 for effecting rotation thereoftogether with a gear 300 also fixed upon said shaft.

A gear 300', driven by the gear 300, is secured to a shaft 304 and actstherethrough to drive two cams which will be herein respectivelyreferred to as the synchronizing cam 306 and the "speed control cam 308.

Contacts 400, 482 and 484 are associated with ,cam 306 and contacts 490,492 and 494 are associated with the cam 308.

Cam 306 comprises a cut-away portion 306 while cam 308 comprises a fullraised portion 308, a semi-raised portion 30B' and a depressed end ofsaid contact 400, for holding same in engagement with said contact 482,except when the cut-away portion- 306 of said cam is situated in thepath of the end of said contact 480, at which time its bias will causeit to move into engagement with contact 4 04 and away from contact 462.l

The contact 490 associated with the cam 306 is situated between thecontacts |92 and 094 and is biased for movement away from the former andinto engagement with the'latter; said 4vcontacts 492 and i3d being sopositioned with relation to said contact 490 that, in the course of themovement thereof, said contact 5130 will break with one before makingwith the other.

The cam 300 is situated in the path of the free end of said contact 490for holding same in engagement with said contact 002 when the fullraised portion 303 of said cam is situated in the path of the end ofsaid contact 090; for holding said contact 030, against the urge of'itsbias, in an intermediate or non-contacting position when the semi-raisedportion 303' of said cam is situated in the path of said end; and forpermitting said contact -to move, responsive to the urge of its bias,into engagement with contact 431i and away from contact @.32 when thedepressed or cut-away portion 3053" of said cam is situated in the pathof said contact.

lt is preferable that the gears 300, 300 shall.

be of such character that simultaneous and synchronical movement will beimparted to the shafts 204 and 304 and the parts carried there-y by tothe end that a cycle of the local controller, as determined by therotation of the `shaft 204, will coincide in all respects with a cycleof the cams 306 and 308 carried by the shaft 304.

The motor MI has a shading coil 290 rotatable with a shaft 3|0foreiecting revisions of the tordue applied to'the disc 292, in a wellknown manner.

Should motor Ml be of a direct current type, as hereinbefore suggested,the shaft 3|0 in rotating may serve to revise the torque of the motor YMI by effecting'revisions in circuit resistance in any well knownmanner.

A disc 322 drives the shaft 3|0 through beveled gears 3|4 and 3|0 and isso associated with the electromagnets M2 and M3 that the excitation ofone of said electromagnets will cause said disc to rotate said shaft inone direction and the excitation of the other of said electromagne'tswill cause rotation of said shaft in opposite direction. For conveniencein description, the electromagnet M2 and the portion of the disc 322associated therewith will be herein referred to as motor M2 and theelectromagnet M3 and its associated portion of the disc 322 will beherein referred to as. motor M3.

From the foregoing it will be evident that energization of motor M2 willcause rotation of the coil 290 in one direction, and energization of themotor M3 will .cause rotation of said coil in the opposite direction.

The permanent magnet 3|8-is associated with disc 292, in a manner wellunderstood by those skilled in the art, to serveas a magnetic brake andthereby maintain a comparatively slow and uniform speed of rotation ofthe disc 292 and to 'further serve to 'minimize coasting by hasteningdeceleration when driving current has been cut off. It will be obviousthat direct current motor mechanism may be utilized in place of the a1-effect closed circuit conditioning upon deenergization of relay llt.Relay H6 has a front contact litt which is engaged by a movable contact|64 upon energization of said relay liti.

The master timer or controller T indicated in the upper portion oi Fig.1 of the drawing above the dash line h comprises a motor M6, ofalternating or direct current type, for driving a gear 600 which, inturn, drives a gear 602 .sci cured to a shaft d. Cams 006 and 608 arealso fixed on said shaft 604. and have cut-away portions and 603 and.raised portions 606" and 000", respectively.

A tracer contact 030 is so associated with the cam 006 and with acontact titi that, when rotation of said cam carries its. raised portion6.06 into the path of said tracer conta-ct, said contact 660 is movedinto engagement with said contact SH2; and, when said raised portion006" r is withdrawn and said cut-away portion 606 is presented, saidContact 6|0 is moved out of engagement with said contact 6|2.

A tracer contact 6M is so associated with the cam 60Btand with a contactBIS that, during presentation of the raised portion 608 of said cam,said tracer contact is separated from said contact BIB; and, when saidraised portion 608" is withdrawn and said cut-away portion 608 ispresented, said tracer contact isznoved to engage said contact 6|6.

Circuit connections The electrical connections provided between themechanisms described are as follows:

Conductors |000 and |002 are for conducting energy from a suitablesource of electric current supply to the master timer T.

The conductor |004 leads from conductor |000 to one terminal of themotor M6, the remaining terminal of motor M6 being connected toconductor |002 through conductor |006, closed switch |000, andadjustable resistance I 0| 0.

The conductor |0| 2 leads from conductor |002 to the contacts 6|2associated with cam 606, and to the tracer contact 6|4 associated withcam 608. Conductors |0|4 land |0|6 lead from contacts 6| 0 and EIS tobus conductors` |032 and |034 respectively.

A third bus conductor |030'is connected to source conductor |000; afourth bus conductor |036 is connected vto source conductor |002 througha normally' closed switch |002; the four bus conductors |030, |032,.|034 and |036 thence extending from the master timer T to and forparallel connection with the synchronizing and speed control systems andmechanisms of each of one or more local controllers. Such connection tobe hereinafter described in connection withthe exemplication of such asystem and'mechanism associated with the single local controllerindicated in Fig. 1.

A further connection at the master timer includes the switch 6|8 which,when closed, conin Fig. 1 ielown the dash line h) comprise theconductors 002 and'022 for conducting energy from a suitable" source ofsupply to such local controller. Such current supply may be either thesame as that to which the conductors |000 and |002 of the master timerare connected, or one which is independent thereof.

Conductor 030 connects one end of Athe wind-` ing of relay 400 withmaster timer bus conductor |032, conductor 040 connects one end of thewinding of relay 462 with master timer bus conductor |034, conductor 030connects the remaining ends o! the'windings of relays 400 and 402 withthe master timer bus conductor |000, a conductor 000 connects conductor036 (and therefore bus |030) with one end of the winding of relay I|6,and a conductor 030 connects the remaining end of such winding to themaster timer bus |030.

At each local controller to be synchronized and speed controlled bymaster timer T, connections corresponding toconductors 030, 040, 036 and030.L should be made. t

Conductor 042 connects source conductor 002 with one terminal of each ofthe motors Ml, M2 and M3; the remaining terminals of which motors arerespectively connected by conductors 000, 046 and 040 with contacts 400,402 and 404.

Conductor 042 connects contact 400 of relay 402 with contact 400 of cam300; conductor 044 connects contact 414 of relay 400 with contact 404 ofcam 000; and conductors 006 and 102 connect contact 412 of relay 400with contact 402 of cam 306. y o

A branch of conductor 192 leads to the movable contact |04 of relay ||0,and a conductor 000 connects the stationary contact |04 of relay ||6with source conductor 022.

Conductor 020 connects the respective movable contacts 404 and 410 ofrelays 402 and 460 with source conductor 022.

Operation as follows:

mm source conductor un, through concluetor |004, motor M0, conductor|006, switch |000,

adjustable resistance |0|0 to current source 4conductor mz.

VOther current paths effective from current source conductor |000 are asfollows: From source conductor |000 through relay 402 by way oi'conductors |030, 030, relay 462. conductors 040. |034 and |0|0, contacts0|6 and 6|4, and conductor |012 to source conductor |002.

Prom source conductor |000 through rely 460 by way of conductors |030,036, relay 400, conductors 030.1032 and |0|4, contacts 0|0 and 0|2 andconductor |0|2 to source conductor 4provided for causing energization ofthe motor MI. Such path leads from conductor 002 through conductor 042,winding of motor MI, conductor 050, contacts 400 and 4,02, conductor192, contacts I 04, |04 and conductor 000 to source conductor 022. ,i

'I'he energization "of motor MI effects rotation of the shaft 294together with the cams 300 and 006. Such rotation causes the cut-awayportion 306 of the cam 306 to be presented to the tracer contact 400,whereupon the previously effective current supply path for the motor Mlis interrupted at contacts 400, 402; the contacts 400, 404 having justpreviously closed in preparation for the establishment of anothercurrent path for subsequent restarting and/or continued operation ofsaid motor.

If, at the time of the interruption ofsuch previously effective currentsupply path of the motor MI, the cams' moving with the shaft 304 aresomewhat in'advance of :synchronism of the mas- From source conductor|000 through relay ||6 by why of conductors |030, 000, 000, relay H0,

. conductors 030, |030 and source conductor |002 adjustment of theresistance- |0|0; the relay I I0 ter timer T, energization of relay 460will cause its movable contact 410 to be separated from itsstationary'contacts 412, 414, and no other energizing current path formotor MI will be immediately available.- The motor MI will therefore bebrought to and maintained atrest until such time as another energizingcurrent path is rendered available through deenergization of relay'400.This stage in the operation of the mechanism is sometimes referred to asthe re-synchronizing period.

Assuming that the master timer T and the shaft 304 and'cams 300, 300 arein synchronism at the re-synchronizing period, as would ordinarily bethe case, the cam 006 of the master timer T fwill. asthere-synchronizing period is about to become effective, withdraw itsraised portion 606" and present its cut-away portion 000' to the tracercontact 6|0, thus permitting this contact to separate from the contact0|2, and thereby break the previously effective current path forenergization of the relay 460.

Following such deenergization of said relay, its contact 410 moves -intoengagement with the contacts 412, 414. 'Iwo paths are thus madeavailable for supplying energizing current to motor MI. Both of thesepaths lead from the source conductor 002 through conductor 042. motorMI, conductor 000, contacts 400, 404, conductor 044, contact 414 tomovable contact 410 where the two paths branch, one leading through themovable contact 410 and conductor 020 to source movable contact 410 tolcontact 412, thence through conductors 000, 102, contacts |64, |04

and conductor 000 to source conductor 022.

'Ihe purpose of these two paths in parallel will be hereinafter morefully explained in connection with the description'of the operation ofthe mechanism without the supervision oi'. a master timer.

When the motor MI thusresumes rotation of the shafts 204, 304 and of thecams 300, 300l the cut-away portion 306 willbe withdrawn and the raisedportion of the cam 000 will be presented for engagement with the tracercontact 400; which contact 400 will therefore move into engagement withthe contact 482 andthereby close the originally described-energizingcurrent path for motor MI, which path will thereafter remain closeduntil ythe cut-away portion 306' of cam 306 is again presented to thetracer contact 480, at the next re-synchronizing period; contact 480being moved away from contact 484 after it has engaged contact 482.

It will be observed that the contour of the cam 606 is such as tomaintain the contacts 6|0, 6|2 in closed relationship throughoutapproximately three-quarters of each revolution of the shaft 604, uponwhich said cam is xed; and that the contour of the cam 608 is. such asto permit closure of the contacts 6|4, 6H;y during approximately 6% ofits rotation, incidental to the latter portion of theclosure of thecontacts 6|0, 6I2.

During the closure of the contacts 6I0, 6|2, just referred to, a currentpath is effective from source conductor i000, through conductors |030,836, relay 468, conductors 838, I|4, contacts 6I0, 6|2

and conductor i0|2 to source conductor i002, for

energizing relay 468.

Similarly, during closure of the contacts 6| 4, 616, a current path iseffective from source conductor i000, through conductors |030, 836,relay 662, conductors 840, i034, l0l6, contacts 6l6, 6l4

and conductor 0l2 to source conductor |002 for energizing relay 462.

The relative times of occurrence and durations of energizations anddeenergizations of the relays 662 and 468, as well as the consequencesthereof 'under `various conditions, are graphically represented in thecharts of Fig. 2.

Between horizontal dashed lines 650 and 652, in the upper portion of thechart of Fig. 2, are lines 660, 660 and 662 representative of thesignificant results of the operation of .the master timer T inestablishing times of occurrence and durations of re-synchronizing andspeed regulating periods; between horizontal dashed lines 652 and 654,the lines 664, 666, 668, 610 are representative of the signicant resultsof the operation of a local' controller in synchronism with the mastertimer T, in terms of the conditioning thereof for response to thecurrent path revisions incidental to the operation of said timer;between horizontal dashed lines 654 and 65,6 the lines 664', 666', 668'and 610' correspondingly indicate results effective in a localcontroller operating at a speed slower than that which would maintain anintended relationship thereof with the master timer; and betweenhorizontal dashed unes 65s and 65s the unes ssa", stuw/,tsarl and 610"correspondingly indicate resul' /eiective in a local controlleroperating at a//Mpeed faster than that which would maintain an intendedrelationship thereof with the master timer.

The space between the dashed vertical lines 620 and 620' isrepresentative of the time of one revolution of the shaft 604 togetherwith the cams 606 and-608 moving therewith, and hence of the intendedtime for a cycle of signal presentations. The Vertical dashed lines 622,624

626, 628, 630, 632 and 634 are .spaced from the line 620 at distancesrespectively representative of approximately 4%, 25%, 50%, '75%, 90%,92% and 98% of the duration of a, signal presentation cycle. l

Returning now to a considerationr of the signicant resultsof theoperation of the master timer T, and associating such results with therepresentatlonsthereof in Fig. 2,-the line 660', extending from verticalline 620 to the vertical line k624, is representative of the time ofoccurrence within the cycle, and the duration, of the separation of thecontacts 640, 6I2 due to withdrawal of the raised portion of the cam606, together with the consequent deenergization of the relay 468, thecontact 410 of which therefore moves into engagement with its contacts412 and 414. For want of a better term, the phrase Special Supply forMotor MI has been applied to this line on the drawing.

The portion of the cycle during which the contact 410 is out ofengagement with the contacts 412, 414 is indicated by the line 660. Theline .662, extending from vertical line 632 to vertical line 634, isrepresentative of the time of occurrence within the cycle, and theduration, of the closure of the contacts 464, 466 of the relay 462,resultant from withdrawal of the raised portion-of the cam 608 from thecontact 6|4, which thereupon engages the contact 6l6.

The line 666,"extending from vertical line 622 to vertical line 620', isrepresentative of the portion of the time occupied by one cycle of theoperation of the master timer T, during which portion a local controlleroperating in synchronism with said timer will have its contact 480 heldin connection with its contact 482 by the raised portion of its cam 306;the line 664, ex-

tending from vertical line 620 to vertical line 622, is representativeof the portion of such cycle during which the contact 480 is permitted(by withdrawal of the raised portion of the cam 306) to engage thecontact 484.

The line 668, which also extends from vertical line 620 to the verticalline 622, is representative of the portion of said cycle during vwhichthe full raised portion 308" of the cam 308 causes the contact 490 toengage the contact 492; and

the line 610 is representative of the portion of said cycle during whichsaid contact 490 is permitted to engage the contact 494, throughpresentation of the'depressedportion 308" of said caml 308 thereto. Inthe portion of such cycle represented by the space between the verticallines 630 and 620', the contact 490 is supported by the semi-raisedsurface 308' in such a position that it does not engage either contact492 or 494, and for this reason neither line 668 nor line 610 extendsthrough this space.

Lines 664', 666', 668 and 610' are representative of lines 664, 666, 668and 610, respectively, for a local controller which is operating at aspeed insuicient to maintain it in synchronism with the mastertimer;.and the lines 664", 666', 668" and 610" are correspondinglyrepresentative for-a local controller which is operating at a speedexceeding that which would maintain it in synchronism with the mastertimer.

Results of relay and contact positionings just described, in View of thecurrent paths established therebetween as hereinbefore more fullyexplained, may be summarized as follows:

A local controller operating in synchronism with the master timer willmaintain continuous operation of its motor MI, and-its motors M2 and M3will not be energized. The continuous operation of the motor MI will beeffected for the reason that (as represented by the synchronousinception of the lines 660' and 664 in.

Fig. 2) upon each occurrence of the resynchronizing period, the currentpath through the convtact 484 will be completed because the relay 468 isdeenergized wheneventhe cut-away portion 306 of the cam 306 is presentedto its contact 480, and said contact 480 has thereupon moved intoengagement with said contact 484 and away nom the positioning of thecontact m (by the.

from the contact' 2. Furthermore. the nonenergisation of the motors M2and MI will result sani-raised portion Ill'nf the cam 3l!) out oi'engagement with the contacts 492 and l, throughout the time when relay 2is energized by closure of the master timer contacts III, lli, resultantfrom presentation of the cut-away portion lll of its associated cam tu.Such cyclic relationship is indicated by the absence of lines l and |10in the portion of the cycle occupied by the line 2, and by recurrence ofthe hnes l and l in relationship 'to vertical line 82|' identical withthat of such lines to the vertical line 82|.

A local controller operating at a speed somewhat less (say not more than20% slower) than that necessary for keeping it in synchronism with themaster timer T, will maintain continuous Operation of its motor Mi andits motor M2 will not be energized However, its motor Ml.

will be energid'during a portion of the cycle vfor the purpose ofrevising the adjustment of the shaft III, and parts controlled thereby,in orderthatthespeedoithe motorMi maybe moderated 'nie continuousoperation of the motor Ml will be veffected for the reason that.whenever the out-away portion III' of its associated cam 3 is presentedto its contact I, and said contact l has thereupon moved into engagementwith the contact l and away from the contact 2, the current path throughthe contact l will be completed because the relay I is at suchtimedeenergiseddue to the contacts III, .I2 of the master timer beingseparated by withdrawal o( the raised portion of the cam ill.

This is represented by the left-hand one of the linesill' which,starting at vertical line 02! simultaneously with the left-hand one ofthe lines nl', falls entirely within the portion of the cycle occupiedby the latter line; and the recurrence or right-hand one of the lines 4',starts to the right of the vertical line 02|'. and, although not havingits inception simultaneously with that of the associated one of thelines ttl', nevertheless falls entirely within that portion of thecyclewhichis represented by saidline lil.

The non-energisation of the `motor M2 results from positioning of thecontact "I away from the contact 2, throughout the energimtion of therelay 2 caused by closure of master timer contacts lll, lll, because thefull raised portion ill" of the cam l does not at that time engage said,contact 0. Inasmuch, however, as the time from the start of the cyclefor the cam tu to carry-m semi-madman ill' into engagement with thecontact. l (as represend by line 810') exceeds the intended time (asrepresented by line 01|) to the extent by which said line 81B' projectsto the right of the vertical line the contact t is permitted to remainin connection with the contact l during a portion of the closure of thecontacts l, l of relay 2, (which portion is represented by the amount bywhich ell extends to the'right cf line O82 and is therefore concurrent A-with a part of the line 2) throughout which portion the motor Mttwillact through the shaft III, the gears llt, III to so rotate the shaft.V`Il as to cause acceleration of themotor MI.

'111e' mcelerating action of motor Mi will be v repeated, as lustdescribed. at the corresponding the cycle of the local controllermechanism operated thereby to catch up with its intended relationshipwith the cycle of the master timer. It is evident that. in bringingabout this result. the speed of the motor Ml will have been so increasedthat, once the cycle of the local controller has overtaken its intendedrelationship to the master timer, the speed of the motor MI will exceedthat which would maintain such relationship. Action will thereforeensue, in a manner which will hereinafter be more fully explained. forsuitably decreasing the speed of said motor MI.

The current path for energizing the motor M3. I

as just referred to, is as follows:

From source conductor 852 through conductor 842, motor M3, conductor l,contacts 494, 490, conductor 942, contacts 466, III and conductor .2l tosource conductor 822.

A local controller, operating at a speed greater than that necessary forkeeping it in synchronism with the master timer T, will have theoperation of its motor Mi suspended during a portion of each cycle, andits motor M3 will not be energized. However, its motor M2 will beenergized during a. portion of the cycle for the purpose of revising theadjustment of the shaft 3l. and the parts controlled thereby, in orderthat the speed of the motor MI may be retarded.

The suspension of the operation of the motor Mi will occur when thecut-away portion 306' of its associated cam 306 is presented to itscontact "l, and such contact has thereupon moved into engagement withthe contact l and away from the contact 482; because the current paththrough the contact l will en be interrupted at the relay 8,energization of which will be sustained due to the contacts Bil, N2 ofthe master timer T remaining closed pending withdrawal of the raisedportion of the cam t.

Upon deenergization of the relay 48|, energization of the motor Mi willbe resumed, so that it will drive the mechanism operable thereby until acorresponding stage is attained in the next succeeding cycle. This isrepresented in Fig.4 2 by line BM", which is shown as starting at apoint in the cycle corresponding with the termination of the line B66and extending to the vertical line 622'.v

- The portion of the line 86E" between its inceprelay 4t2, asrepresented by the line 662.

The energization of the motor M2 results from the closure of thecontacts 490. 492 during a portion of the energization of the relay 2,as indicated inlligi 2 by the distance which the line "l" extends to theleft of the vertical line IN. Throughout such energization, said motorM2 will so rotate the shaft SIU as to cause retardation of the motor Ml.Such retardation will thereafter be repeated in the corresponding stageof each succeeding cycle until the speed of the motor Ml has been sodecreased that the stage of the cycle of the local controller assumesits intended relationship to the cycle of the master afoise i 7 timer.It is evident that, in bringing about this result, the speed of themotor M| will have been so decreased that, once the cycl/ of the localcontroller has thus attained irrt/ended relationship with the mastertimer/the speed of said motor M| will be insufficient to maintain suchrelationship. Action r,will therefore ensue in a manner hereinbefore'more fully described for suitably increasing the speed of motor MI.

The current path for energizing the motor M2 as just referred to is asfollows:

From source conductor 852 through conductor 842, motor M2, conductor946, contacts 492, 490, conductor 942, contacts 466; 464 and conductor820 to source conductor 822.

Under ordinary operating conditions, the regulating actions which havejust been described are not of extensive amplitude. If, however, a localcontroller has, by any means, gotten greatly out of step with the mastertimer, so that extensive rotation of the shaft 3|0 occurs before anapproximation of synchronism is attained, a

so-called hunting actionvof the speed control` ling mechanism ofprogressively decreasing amplitude will continue until an adjustment ofthe shaft 3|0 has been attained which will cause operation of the motorMI at a speed such that the cycle of the local controller willsubstantially coincide With that of the master timer.

if it is desired to lengthen or shorten the cycle time of the associatedcontrollers, this may be done by varying the resistance |0||l at themaster timer whereupon the speed of the motor M6 will be correspondinglyaltered, with resultant revision of the positionings of the speedregulating shading coils 290 of the motor MI of all local controllers,in a manner hereinbefore more fully explained.

Should it be desired that the operation of the local controller besuspended, switch 6| 8 Should be moved to closed position, thuseffecting continuous energization of relay 468 to cut off the normalcurrent supplyto motor MI. Furthermore, switch |002" should be opened topermit deencrgizati on of relay I6, thus opening the path throughcontacts |64, |04 to motor MI.

In practical use, it has been found desirable that all current paths forthe signal lights, motors, relays, etc., which lead from each localcontroller to source conductor 822 shall pass through its associatedcontacts |64, |04. Such practice enables the deenergization of relay I6during energization of relay 468'to effect complete suspension ofall/activities of the associated local controller'and its synchronizingand speed control system and mechanism, and to extinguish the signallights.

The foregoing descriptions have been, for the most part, based upon theassumption that mechanism such as that shown below the dashed line h inFig. l is to be utilized irl-conjunction with a master timer such asthat shown above the dashed line h in Fig. l; however, controllerssupervised or governed in accordance With this invention may be placedin service Without providing any connection therefrom with a mastertimer, as when installed at an isolated intersection or location soremotely situated with reference to other intersections or pointsneeding trafc control as to in no way require master timer supervision.

Controllers supervised or governed in accordance with this invention, ashereinbefore more fully described, will maintain efficient operationeven in the event of discontinuance of a previously effectiveresynchronizing or other connection with a master timer. Thus, shouldthe benefits of a master timer be dispensed with or should power failureor circuit trouble interrupt the supervision of the local controllermechanism, such mechanism would continue operating at the speed lastdetermined by the positioning of the shading coil 290'; motor Ml beingcontinuously energized, irrespective of the positioning of contact 480,because of continuous deenergization of relay 468 and resultantengagement of its movable contact 410 with the stationary contacts 412and 414. In such an event, if all of the current paths for the signallamps, motors and relays of the local controller4 pass through contacts|64, |04, (as hereinbefore indicated as desirable) current flow for suchmotors, lamps and relays from source conductor 822 will passuninterruptedly from such conductor 822 through conductor 820 contacts410 and 412, conductors 896 and.'|92 to contact |64 at which point thepath branches to lead through the various motors, lamps, relays andcontrolling circuits to the source conductor 852.

It will be evident from the foregoing that this i.

invention might have been illustrated in the accompanyingdrawing asembodied in any one of many different kinds of mechanism. That which hasbeen selected for use as illustrative of the invention has been chosenas a matter of coni; venience, and not because it exhausts the scope oftheinvention in its application to the various uses for which it issuited. Furthermore, it should be remembered that various features ofthis invention may be advantageously utilized singly or in I.

groups containing less than all of said features.

The explanations hereinbefore given as to illustrative applications ofthis invention to certain of the many possible uses thereof, whenconsidered in connection with the accompanying drawing, are believed tobe fully sufficient to enable those skilled in this art to readily applythis invention to all situations to which it is suited.

Claim is made to, and it is desired to secure by Letters Patent of theUnited States of America, all generic and specific features of theinvention shown by the accompanying drawing and as hereinbefore morefully described,.including all features which may, as a matteroflanguage, bc said to fall between the scope of any of the folf.'

lowing claims.

We claim:

l. In a synchronizing and speed control system, means for periodicallyformulating impulses in respective ones of two channels, controlledmech- V:

anism having a predetermined cycleof operation and including a variablespeed driving motor, means associated with one of said channels andrendered effective during each cycle of said mechanism for synchronizingsaid mechanism responsive to impulses of said Lormulating means in saidone of said channels, means associated with and renderedresponsive toimpulses in the other of said channels at predetermined stages in eachmeans for periodically formulating impulses in respective ones of twochannels, controlled mechanism having a predetermined cycle of operationand including a variable speed driving motor, means associated with oneof said channels and effective during each cycle of said mechanism forsynchronizing said mechanism responsive to impulses of said formulatingmeans in said one of said channels, means associated with and responsiveto impulses in the other oi' said channels for increasing or decreasingthe speed of the driving motor resultant from premature or tardy time ofattainment of predetermined stages in the operating cycle of saidmechanism with respect to the time of occurrence of impulses in saidother channel whereby the speed of said motor will be governed forsubstantially maintaining predetermined relationship between formulationof impulses and cycles of controlled mechanism operation.

3. In a synchronizing and speed control system, means for periodicallyformulating impulses, controlled mechanism having apredetermined cycleoi operation and including a variable speed driving motor, meanseilective during each cycle of said mechanism for stopping csaidvariable speed driving motor, means responsive to said impulses forrendering said stopping means in-l effective when said driving motor issubstan-` tially in step with said periodic impulses, means responsiveto said impulses for increasing or de-l creasing the speed of saiddriving motor resultant from premature or tardy time of attainment of.predetermined stages in the operating cycle of said mechanism withrespect to the time of occurrence of said impulses whereby the speed ofsaid motor will be governed for 'substantially Vmaintainingpredetermined relationship between Iformulation of impulses and cyclesof controlled mechanism operation.

4. In a synchronizing and speed control system, means for periodicallyformulating impulses in respective ones of two channels, controlledmechanism including a variable speed driving motor, means associatedwith one of said channels and rendered effective incidental to operationof said mechanism for synchronizing said mechanism responsive toimpulses of said formulating means in said one of said channels, meansassociated vwith and rendered responsive to impulses in the other ofsaid 'channels at predetermined stages in the operation of saidmechanism for increasing or decreasing the speed of said driving motorresultant from premature or tardy time of attainment of such stages withrespect to the time of occurrence of impulses in said other channelwhereby the speed of said motor will be governed for substantiallymaintaining predetermined relationship between formulation of impulsesand attainment of such stages of controlled mechanism operation.

5. In a synchronizing and speed control system, a master timercomprising a constant speed driving motor, a shaft driven byV saidmotor, camssecured to said shaft, contacts associated with said cams andperiodically actuated thereby, a resynchronizing channel periodicallyenergized and deenergized responsive to contacts associated with one ofsaid cams, and a speed control channel periodically energized anddeenergized responsive to contacts associated with another one of saidcams; a controlled mechanism comprising variable speed motor, a shaftdriven by said mechanism motor, cams secured tosaid mechanism shaft,contactsassociated with said mechanism cams and periodically actuatedthereby, means associating said re-synchronizing channel with theIcontacts associated with one of said mechanism cams for rendering saidlre-synchronizing channel effective to synchronize said mechanism duringa concurrent predetermined conditioning of said re-synchronizing channeland of the contacts associated with said one of said mechanism cams,means associating said speed control channel with the contactsassociated with another of said mechanism cams for rendering said speedcontrol channel eifectively associated for causing alteration of theJspeed of said variable speed motor during a concurrent predeterminedconditioning of said speed control channel and of the contactsassociated with said other one of said mechanism cams and meansresponsivey "to said effective association therewith of said speedcontrol channel for altering the speed of said variable speed motor.

6. In a synchronizing and speed control system, f' means forperiodicallyformulating impulses, a

controlled mechanism having a cycle of operation oi predetermined lengthand including a variable speed driving motor, means eifective duringeach cycle of said mechanism for synchronizing the cycles of saidmechanism responsive to said formulating-means impulses, meansmechanically connected with said driving motor and responsive to saidimpulses for exerting a force to cause increase or decreasel in thespeed of said driving motor resultant from premature or tardy time ofattainment of predetermined stages in the operating cycle oi saidmechanism-with respect to the time of occurrence of said impulseswhereby the speed of said motor will be governed for substantiallymaintaining predetermined relationship between formulation of impulsesin the cycles of controlled mechanism operation.

7. In a synchronizing and speed control system, the combination ofperiodic impulse formulating means, means for controlling the speed ofthe periodic impulses, controlled means including a driving. motorhaving a shading coil movable for eilecting adjustments in the speedthereof, a second motor for moving said shading coil in one direction orthe other, means jointly responsive to impulses of said formulatingmeans and to said controlled means for causing said second motor to movesaid shading coil in one direction or the other, and means responsive tolack of synchronization between the impulse formulating means and thecontrolled means for deenergizing the shading coil.

HARRISON IRVING TURNER. CARL LUDWIG ANDERSON.

